Mermaid sequence diagram in Markdown to PDF

---
title: Operations note, card payment at checkout
author: Payments team
---

# Operations note: card payment at checkout

For the payments team and for agents who take calls about a declined or duplicated payment. It describes the checkout flow in use since 1 March 2026 and stays the reference until it is replaced.

A payment is authorized when the order is placed and captured when the parcel is handed to the carrier. Nothing is captured before dispatch, so a cancelled order never needs a refund, only a release of the authorization.

## The flow

```mermaid
sequenceDiagram
  autonumber
  actor C as Customer
  participant S as Shop
  participant P as Payment provider
  participant B as Card issuer

  C->>S: Place order
  activate S
  S->>P: Authorize amount
  activate P
  P->>B: Authorization request
  B-->>P: Approved or declined
  deactivate P

  alt Approved
    P-->>S: Authorization code
    S-->>C: Order confirmed
    Note over S,P: Capture happens at dispatch, up to 7 days later
  else Declined
    P-->>S: Decline reason
    S-->>C: Ask for another card
  else Needs customer verification
    P-->>C: Verification challenge
    C->>P: Code from the banking app
    P-->>S: Authorization code
    S-->>C: Order confirmed
  end
  deactivate S

  loop Each evening until the parcel ships
    S->>P: Is the authorization still valid
    P-->>S: Days remaining
  end

  par At dispatch
    S->>P: Capture amount
    P-->>S: Captured
  and
    S->>C: Dispatch email with tracking
  end
```

## What can go wrong

| Symptom the customer reports | What happened | What the agent does |
|------------------------------|---------------|---------------------|
| "I was charged but have no order" | The authorization succeeded, the order step failed | Release the authorization. The hold disappears within 5 working days |
| "I see two charges" | The customer retried after a verification timeout | Check both authorizations. Release the one without an order |
| "My card was declined" | The issuer declined | Say only the reason the issuer gave. Never guess at the cause |

> [!WARNING]
> Never capture by hand before dispatch. A capture without a dispatch scan is a chargeback waiting to happen, and the carrier's scan is the evidence we rely on.

## Figures for March 2026

| Line | March 2026 |
|------|-----------:|
| Authorizations requested | 412,300 |
| Approved at the first attempt | 93.4 % |
| Sent to customer verification | 4.8 % |
| Declined | 1.8 % |
| Captured within 7 days | 99.1 % |

*All organizations in the sample documents are invented. Names and figures are illustrative.*